66353813 has 2 divisors, whose sum is σ = 66353814. Its totient is φ = 66353812.

The previous prime is 66353797. The next prime is 66353821. The reversal of 66353813 is 31835366.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 52388644 + 13965169 = 7238^2 + 3737^2 .

It is a cyclic number.

It is not a de Polignac number, because 66353813 - 2⁴ = 66353797 is a prime.

It is a super-3 number, since 3×66353813³ (a number of 24 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66353863) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33176906 + 33176907.

It is an arithmetic number, because the mean of its divisors is an integer number (33176907).

Almost surely, 2^66353813 is an apocalyptic number.

It is an amenable number.

66353813 is a deficient number, since it is larger than the sum of its proper divisors (1).

66353813 is an equidigital number, since it uses as much as digits as its factorization.

66353813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 38880, while the sum is 35.

The square root of 66353813 is about 8145.7849836587. The cubic root of 66353813 is about 404.8448585278.

The spelling of 66353813 in words is "sixty-six million, three hundred fifty-three thousand, eight hundred thirteen".